Gun installation



w.. B. KLEMPERER 2,359,994

GUN INSTALLATION Filed Nov. 20, 1939 3 Sheets-Sheet 1 Zinnentor: W01 6mm & Mia/252m R E R E P M E L K B w GUN INSTALLATION Filed NOV. 20, 1939 3 Sheets-Sheet 3 Patented @ct. i0, 19%

FFECE GUN WSTAILLA'EEON Wolfgang B. Klemperer, Los Angeles, Caliit, as-

signer to Douglas Aircraft Company, linc., Santa Monica, Calif., a corporation of Delaware Application November 20, 1939, Serial No. 305,273

12 Claims.

My invention relates to armament wherein a gun and gun sight are associated for direct cooperative use in the aiming of the gun at a visible target, and relates in particular to a novel and improved gun sight enabling greater freedom in the gunnery art in the selection of gun emplacements.

It is an object of the invention to provide a gun sight which may be used in conjunction with a. gun in restricted quarters and in places where movement of .the gunner is restricted, for example, in the tail structure or nacelles of an aircraft. The invention is likewise of utility wherever it is desired to mount the gun sight stationary so that the gunner need not move his body or head from a fixed position.

This application is a continuation in part of my copending application filed October 23, 1939, Serial No. 300,789, for Gun installation, which issued as Patent No. 2,281,772, May 5, 1942, wherein the conditions encountered in the installation of a gun in the tail structure of an aircraft or other confined space are illustrated and described in detail. Therein it is shown how a gun may be mounted in a position to project rearwardly from the tail of an aircraft with the gunner occupying a space in the tail structure of such small size that his movement from one position is restricted, so that he is prevented from moving his body in a way required to keep his eye applied to the eyepiece of a telescope mounted directly upon a gun which is pivotally mounted soastobeaimedatpointsinafieldlyingto the rear of the aircrafts tail structure. In the present invention 1' have provided means whereby the articulation of the gun may be separate from that of the gun sight, so that as the gunner swings the gun for purpose of aiming, he need not move his head from a single convenient position in use of the gun sight as a means for detering the aiming 11.. vement of the gun.

It is an object of the present invention to provide a. gun sight equipped with optical means establishing an optical axis along which a light image may pass from the field of vision to the eye of the gunner, this gun sight havingmeans preferably at the front or far ends thereof and having operative connection with the movement of the gun or gun body whereby the projected portion or the optical axis may be bent, deflected, or swung in keeping with the swinging movement of the .gun as it isaimed, and'whereby the projected portion of the optical axis will intercept the point in the field at which the gun is aimed. It is an object of the invention to provide-in conjunction with a gun which is swingably mounted for purpose of aiming, a swingable image receiving or transmitting element which receives an image from a field in which 'the gun is aimable, this image passing to the image receiving element along an image receiving axis which is defined by the position of the image receiving element, andin operative association with the image receiving element 'there is substantially stationary optical means for carrying the image to the eye of the gunner who need not change the position of his head as the gun and the image receiving element are swung in cooperative relation. In the invention the gun and theimage receiving element are connected so that the image receiving axis is always substantially parallel to the axis of the gun barrel. Accordingly, when the gun is aimed at a point in the field, the image receiving axis will be directed at this point in the field, and the image thereof will pass back along the image receiving axis to the image receiving element and then be transmitted by the stationary optical means to the eye of the gunner. In further explanation it may be stated that as the gurmer swings the gun in any direction within its range of movement, the field of vision presented to the eye of the gunner travels with the point at which the gun is aimed. Thus,

the center point of the field of vision presented to the eye of the gunner will coincide with the aim point of the gun. Although the gunner is not required to move his body and head from a position of rest, there is brought to his vision an image which moves with the aiming point of the gun, as the gun is swung. This image at all times has at substantially the center thereof the aiming point of the gun, which aiming point may be defined as the point where the field is intersected by the axis of the gun or the line of travel or trajectory .of the projectile fired therefrom. The alignment between line of sight and gun may, however, be subjected to corrections which are deliberately introduced to compensate. for the factors of kinematic, phoronomic, trajectory drop and other inherent ballistic considerations.

It is a further object of the invention to provide for use with a. pivotally mounted gun a gun sight having a support pivotally mounted at the farend thereof so as to swing on an axis, and a vlslondirecting element pivotally carried by'the support so as to swing on a second axis which lies in crossing relation to the first axis, and means for producing cooperative swinging movement ofthe support and of the vision directing element so as to swing the image receiving axis in accordance with the swinging of the gun as the same is aimed. In a preferred form of my invention the vision directing means may comprise a mirror or mirrors disposed in angled relation to the axes along which the image is directed. Under some conditions, however, the vision directing means may comprise a prism.

Further objects and advantages of the invention will be brought out in the following part of the specification.

Referring to the drawings which are for illustrative purposes only:

Fig. lis an elevational view showing a preferred form of my invention.

Fig. 2 is an enlarged face view partly sectioned on the line 2-2 of Fig. 1.

Fig. 3 is an enlarged cross-sectional view of the optical axis directing means, taken substantially a indicated by the line 3--3 of Fig. 2.

Fig. 4 is a sectional view showing an alternative formof the optical axis directing means.

Fig. 5 is a sectional view showing a form of optical axis bending mean wherein both the mirror and window of the device are mounted in a rotatable frame.

To illustrate the general type of small housing in which the invention may be employed, I have in Fig. 1 outlined in broken lines l9 the tail structure of an aircraft having doors I I swingable on hinges |2 between closed and open relation, as fully described in my copending application. A gunner l3, seated in the housing I swings a gun |4 carried by a universal support 5 in any desired direction from a mean gun axis l4, to aim the same at a target in a field lying to the rear of the tail of the aircraft. The supporting means |5 comprises a yoke l8 having vertical members which have bearing members l3 lying on a horizontal axis and receiving stub shafts |9 which project outward from a cradle 20 ,in which the gun I4 is removably secured.

The yoke It has top and bottom members 2| and 22 from which stub shafts 23 and 24 extend o as to be received in bearings 25 and 29 defining a vertical axis. Accordingly, the gun I4 and the'cradle 20 may have universal movement in a limited range, therebeing rotation of the trunnions l9 in accordance with the vertical swinging component, and rotation of the yoke IS on the vertical axis defined by the stub shafts 23 and 24 in accordance with the horizontal component of the swinging movement of the gun in aiming the same at a target.

A gun sight 2'! is secured by means of brackets 29 and 29 above the butt end of the gun l4 and in such position that the eyepiece 30 thereof will be convenient to the eye of the gunner I3. The gun'sight' 21 comprises a telescope having lenses defining an optical axis 3| along which an image is carried to the eye of the gunner and a reticule 3| through which the image passes. The optical I axis 3| is referred to as having an inner section or portion 32 and an outer or projecting portion 33 which extends to the field of vision lying to the rear of the aircraft tail structure. The inner section 32 of the optical axis extends along the mean gun axis l4, in the sense that it extends in the same general direction as the mean gun axi l4. In the example of a preferred form of my invention I have shown the section prescribed relation (substantially parallel) to the firing axis of the gun l4. The following description of the optical axis directing means 35 refers expressly to Figs. 2 and 3 wherein the parts thereof are shown to enlarged scale. The light receiving end 34 of the gun sight 21 is provided with a frame 38 which supports a reflector, shown as a mirror 31, in a position adjacent the objective lens system 38 of the gun sight 2! to intercept the path of the inner axis section 32 and bend the far or external end 32' of the axis section 32 upward by reflection. The mirror 31 is so positioned that the upwardly directed end portion 32' of the axis 32 will either coincide with or be parallel to the axis AA defined by the stub shafts 23 and 24 of the yoke IS.

A second light bending element, in the form of a mirror 39, i mounted above the mirror 31 in such position that it will be impinged by the end portion 32 of the axis section 32, and so that it may have universal movement whereby it may be rotated around or on the end 32' of the axis 32 or rotated on an axis B-B dis sed in crossing relation to the axis AA.

The position of the mirror 39 relative to the mirror 31 determines the position of the projecting portion 33 of the axis 3|. When the mirror 39 is parallel to the mirror 31, a shown in full lines in Fig. 3, the projecting portion 33 will be parallel to the inner portion 32. When the mirror 39 is rotated either clockwise or anti-clockwise around the axis BB, as shown in dotted lines 33a and 39b in Fig. 3, the axis 33 will be swung either downward or upward as indicated respectively at 33a. and 33b. When the-mirror 39 is merely rotated about the axis A- 'A without changing the angle of the mirror relative to the end portion 32' of the inner axissection 32, the projecting portion 33 of the optical axis will be swung to a side of its position parallel to the inner portion 32.

The means for supporting the mirror 39 so that it, may have the universal swinging movement hereinbefore described includes an upright rec tangular frame 40 having lower and upper pivot means 4| and 42 disposed on the axis A-A. The

lower pivot means 4| comprises a shaft whichis fixed in the lower portion 43 of the frame 40 by means of a pin 44. The upper pivot means 42 comprises a vertical screw which is threaded downward into the upper portion 45 of the frame 32, Fig. 1, substantially parallel to the mean gun axis |4'. At the light receiving end 34 of the gun sight 21 there is a means 35 for automati-' 49. The members 4| and 42 pass respectively through openings 46. and 41 in the support 35. The upper portion 45 of the yoke 49 comprises a sloping wall and at the upper outward edge thereof has a pair ofspaced downwardly projecting brackets 49 provided with openings on the axis B-B to receive stub shafts 50 and 5| which project laterally from aplate 52 which carries the mirror 39. A pulley 55, fixed on the projecting end of the shaft member 5| is connected through a loop cable 55 with a spool 51 fixed on the pro- Jecting stud 53 of one of the trunnions l9, to accomplish swinging of the mirror 39 about the axis 2B'B and to different angles relative to the axis A-A, in accordance with the vertical swinging movement of the gun l4. The shaft member 4| at the lower end of the frame 49 has at its lower end a joint 59 whereby it is directly connected to the upper end of the gun shaft 23 of the yoke It in which the gun I4 is mounted. Accordingly, horizontal swinging movement of the gun in either direction from the mean gun axis I4 is transmitted through the yoke IS, the shaft member 23, and the shaft member 4| to the yoke #38, to rotate the yoke 40 and the mirror 99 on the axis AA in direct angular relation to the lateral swinging of the gun 4|.

Owing to the direct connection of the yoke l6 and the frame 60, as pointed out in the foregoing, the spools or pulleys 55 and swing in unison about the axis AA and the operative alignment thereof is at all times maintained. The spool55 has a diameter twice that of the spool 5'! so that the angular movement of the mirror 39 will be half of the vertical angular movement of the gun l4 as'it is swung on the horizontal trunnions l9, thereby maintaining substantial parallelism of the projected por-, tion 33 of the optical axis and the axis of the gun IE. For example, when the gun It is pointed downward from the mean gun axis 54', as along the axis Ma of Fig.- 1, the projecting portion of the optical axis will swing down into the position indicated at 33c, and when the gun is pointed upward from the mean gun axis id, as along the axis Mb, the projecting portion of the optical axis will swing up to the position indicated at 33b. At the same time any lateral excursion of the axis of the gun hi will be accompanied by a like lateral deflection of the projecting portion 33 of the optical axis, with the result that the center of the image transmitted to the eye of the gunner will intercept or coincide with the aiming point of the gun in the field in which the gun may be aimed. It is recognized that in many uses of the invention, it will be desirable to incorporate means for correction of factors involved in the aiming of a gun at a target by use of optical gun sight means. This disclosure has been maintained as simple as reasonably possible so as to bring out the essentials of the invention, but it is intended that wherever necessary in the use of the invention provisions for correction and adjustment will be employed in conjunction with the essential elements of the invention in the general manner disclosed in my copending application hereinbefore referred to, or in accordance with the general knowledge of the art of gunnery.

In Fig. l of the drawings, I have shown a glass window 65 supported by means of a frame 66 on the tail structure in of the aircraft, through which window light may pass to the reflector 39 from the field of vision. bending means supported within a housing mounted on the front end 68 of a telescope 69 having an objective lens system 70 therein. The housing ii is mounted on the telescope 69 by means of a cylindrical wall 12 having an opening to receive the end of a telescope 68, and having walls it and i5 defining a space to receive In Fig. 4, I show light.

this gear segment 82 is engaged by a rack 83 carried by a rod 84 which passes axially through the hollow shaft 8| of the bracket 80. Vertical movement of the member 84 in accordance with the vertical swinging movement of an associated gun will swing the reflecting element 11 so as to change its'angle relative to the axis A--A. The optical axis 85 of the gun sight 69 impinges the reflecting element It and is reflected to the element Tl which in turn directs the optical axis 85 out through the window T8 at different angles or in parallel relation to the center line of the gun sight 89, in accordance with the position of the reflecting element 11 relative to the reflecting element '36.

For illustrative purposes only, I have in Fig. 4 shown a manner of connecting the bracket 80 and the rack 83 so that they will be moved in response to lateral and vertical movements of the gun. A gun fld'is shown vertically swingable on pivot means 89' in a yoke 15' in a manner similar to the disclosure 'of Figs. 1 to 3 inclusive. The hollow shaft 8! is engaged by the upper end of a stub staft 23 so that rotation of the bracket 15 willresult in a like rotation of the bracket 89 and the mirror TI on the vertical axis AA. The rod 84 extends through an axial opening 99' in the stub shaft 23 and its lower end is engaged by a cam 51a which is connected to the gun it so as to rotate therewith around the pivot means H) as the gun It is swung verprimary and secondary reflecting elements 76 and 11, the reflecting element 16 being mounted in diagonal relation adjacent the objective lens system 10, and the reflecting element 77 being disposed in cooperative relation to a window 18 carried in the front wall portion of the housing ll. The reflecting element I! is mounted on a shaft i9 supported in a swinging bracket or head 89 having a hollow shaft fll'which projects downtically. The cam is formed so that in cooperation with the rack 83 and the gear segment 82, the mirror ill will be rotated on the pin l9 through anangle substantially half the angle which i traversed by the gun M.

In Fig. 5 I show an alternative form of my invention wherein the housing containing one of the light bending elements is rotatably mounted. In the forms of the invention previously disclosed both of the mirrors of the vision directing means have been placed outside the objective lens system. In Fig. 5 I show a mirror 90 disposed at the end of a telescope or gun sight tube 95, the objective lens system 92 of thegun sight being supported in a tubular housing 93 in perpendicular relation to the member 9|. A

housing 99 is provided having a ring 95 which to the mirror 9'! in a position to be engaged by a rack I00 formed on a bar Hll which passes through a guiding boss I02 of the housing 94.

The housing 99 is connected directly to the stub shaft 23' so that as the lateral movement of the gun rotates the yoke 85', the housing and the variant contained mirror 91 will be given like rotation on the axis A-A. The rack I00 is connected by the rod or bar l0! with a vertically movable rack III! which is engaged by a gear HI which is connected to the gun I4 so as to have. vertical angular movement in accordance with the vertical swinging of the gun l4 around the pivot means l9, the radius of the gear' III being substantially half the radius of the gear segment 99 so that the angular movement of the mirror 9'! around the axis of the pivot means 98 will be through an angular distance one-half the swinging movement of the gun Id.

In the operation of the form of the invention shown in Fig. 5, the optical axis H05 impinges the mirror 90 which reflects it at substantially right angles through the objective lens system 92 as indicated at I05. The mirror 91 directs the optical axis through the window 95. The swinging of the projected portion lllia of the optical axis is accomplished as follows. The mirror is rotated about the axis A,A by rotating the housing 94 on the member 93, and swinging of the mirror 91 on the lateral axis defined by the pivot means 98 is accomplished through vertical movement of the bar llll carrying the rack Hill to engage the gear segment 99. In this form of the device the window 96 swings with one direction of movement of the projecting portion I051: of the optical axis, namely, the lateral swinging movement. I

I claim as my invention: 7

1.-In armament of the character described, the combination of a main support; a gun; swingable means supporting said gun for universal movement on said main support whereby said gun may be aimed; a gun sight supported on said main support independently of said gun, said gun sight having optical means, stationary relative to said-main support, to define an optical axis, the inner portion 'of which is stationary relative to said main support and the outer portion of which extends outward from the gun sight to a field of vision; and universally swingable control means for swinging said outer portion of said axis relative to the inner portion thereof, said control means being connected to said swingable means so that there will be a like swinging movement of said control means and said gun swung so as to substantially coincide with the point in said field at which said gun is at any time aimed.

2. In armament of the character described, the combination of: a gun; swingable means universally supporting said gun so that it may be swung in all directions from a mean gun axis,

whereby said gun may be aimed; a gun sight supported independently of said gun, said gun sight having optical means to define an optical axis, the inner portion Of which is relatively stationary and extends in side by side relation to said gun axis and the outer portion of which ment of said gun from a centralized Dositioncoinciding with said gun axis will be accompanied by a similar swinging movement of said outer portion of said axis.

3. In armament of the character described, the combination of: a stationary gun sight having a reticule on an optical axis; a gun mounted for universal movement-relative to said axis and said reticule whereby said gun may be aimed at points in a. field; and universally movable optical means associated with said gun sight and moving automatically in accordance with the move-' ment of said gun t bring to said reticule the image of any-point in said field at which said gun may be aimed.

4. In armament or the character described,

the combination of a stationary gun sight hav-' ing means to establish an axis'along which an image is directed to the vision of a gunner; a gun mounted so as to be universally movable relative to said axis and whereby it may be aimed at diflferent points in a field; and light bending means universally movably associated with said gun sight so as to direct along said axis to the vision of the gunner an image of'that portion of gun mounted so as to be universally movable rel ative to said axis and whereby it may be aimed at diiferent points in a field; and universally 'swingable reflecting means associated with said gun sight and having means connecting it with said gun whereby it will be swung in accordance with the movement of said gun so as to direct along said axis to the vision of the gunner an image of that portion of said field at which said gun at any instant may be aimed.

6. In armament of the character described, the combination of: a stationary gun sight having means to establish an axis along-which an image is directed to the vision of a gunner; a gun universally mounted so as to be aimed at different points in a field; a reflector universally pivotally mounted at the far end of said gun sight; and means connecting said gun and said reflector sothat said reflector will have movement. in accordance with the movement of said gun whereby it will direct along said axis to the vision of the gunner an image of that portion of said field at which said gun may at the instant be aimed.

7. In armament of the character described, the combination of: a gun sight having means to establish an axis along which an image is directed to the vision of a gunner, said gun sight having a far end faced in the general direction of the object to be sighted; a gun mounted so as to be universally swung relativerto said axis and whereby it may be aimed at different points in a field; a support pivoted on a first axis near the far end of said gun sight; light bending means pivoted on said support so as to swing on a second axis disposed in crossing relation to said first axis; and means having connection with said support and said light bending means and operating in accordance with the swinging of said gun to swing said light bending means on said second axis and said support on said first axis so that said light bending means will at all times direct along said optical axis to the vision of the gunner, the image of that portion of said field at which the gun is aimed.

-8. In armament "of the character described, the combination of: a stationary gun sight hav- 'ing means to establish an optical axis along which an image is directed to the vision of a gunner, said gun sight having a far end faced in the general direction of the object to be sighted; a gun mounted so as to'swing relative to first and second axes disposed in crossing relation, whereby the gun may have universal aiming movement; a support carried by pivots at the far end of said gun sight; a mirror supported on pivots in said support disposed so as to be on a line having crossing relation to the line defined by said first named pivots so as to have universal swinging movement resulting from the swinging of said mirror and said support on their respective pivots; means connecting said gun and said support so that movement of said gun on said first axis. will swing said 2,359,994 a Lie support; and means connecting said gun and said mirror whereby movement of said gun relative to said second axis will swing said mirror on said support.

9. In armament of the character described, the combination of: a gun sight having relatively stationary means to establish an optical axis along which an image is directed to the vision of a gunner, said gun sight having a far end faced in the general direction of the object to be sighted; a gun mounted so as to swing relative to first and second axes disposed in crossing relation and in any direction from a gun mean axis which is maintained in fixed space relation to said optical axis, whereby the gun may have universal aiming movement; a light bending element at the far end of said gun sight and being disposed in crossing relation to said optical axis; means operating automatically to rotate said light bending means without changing its angle relative to said optical axis when said gun is swung relative to said first axis; and means for automatically changing the angle of said light bending means relative to said optical axis when said gun is swung relative to said second axis.

10. In armament of the character described, the combination of 1 a gun; means for mounting said gun so that it may be swung in any direction from a mean gun axis, said mounting means comprising first pivoted'means swingable on a first line disposed in crossing relation to said axis, and second pivoted means swingable on said first pivoted means on a second line disposed in crossing relation to said first named line and said axis; a gun sight adjacent said mounting means comprisinga support carrying optical means disposed so as to define an optical axis extending along said mean gun axis, along which axis an image of the field ahead of said gun passes, and light bending means universally supported at the far end of said support and intercepting said optical axis; means connecting said light bending means and said firstpivoted means so that swinging of said first pivoted means on said first line will swing said light bending means on a line substantially parallel to said first line; and means connecting said light bending means and said second pivoted means so that swinging of said second pivoted means on said second line will swing said light bending means on a line substantially parallel to said second line.

11. In armament oi the character described, the combination of: a gun; means for mounting said gun so that it may be swung in any direction from a mean gun axis, said mounting means comprising a yoke swingable'on a first. line disposed in crossing relation to said axis, and a gun bracket swingable on said first pivoted means on a second line disposed in crossing relation to said first line and said axis; a gun sight adjacent said mounting means comprising a support carrying optical means disposed so as to define an optical axis extending along said mean gun axis, along which axis an'image of the field ahead of said gun passes, and light bending means at the far end of said support, said light bending means comprising a frame mounted so as to swing on a line parallel to said first line and a reflector mounted in said frame so as to swing on a line parallel to said second line and in a position to intercept said optical axis; means connecting said frame and said yoke so that swinging of said yoke on said first line will swing said frame; and means connecting said reflector and said bracket so that swinging of said bracket on said second line will swing said reflector in said frame, said lastnamed means comprising a pulley connected for rotation to said bracket, a pulley connected to said reflector so as to rotate the same, and over-running means connecting said pulleys so that rotation will be transmitted from the first to the second'pulley.

12. In sighting means adapted for use with a gun mounted on a support for universal swinging movement so as to be aimed at points in a field, the combination of a gun sight adapted to be secured to said support so as to be substantially stationary during the aiming of the gun, said gun sight having an internal axis and an external axis cooperating to define a pathof light to the eye of a gunner from an object; optical means universally swingable relatively to said 'gun sight for swinging said external am's relative to said internal axis; and means adapted to connectv said optical means and the gun so that said optical means will be swung in accordance with the swinging of the gun, whereby said external axis will be swung so as to coincide with the point in said field at which the gun is aimed. 

